Author/Authors :
Ichihara، نويسنده , , Junko and Yamaguchi، نويسنده , , Shunro and Nomoto، نويسنده , , Takuya and Nakayama، نويسنده , , Hirokazu and Iteya، نويسنده , , Katsuma and Naitoh، نويسنده , , Nozomu and Sasaki، نويسنده , , Yoh، نويسنده ,
Abstract :
We found that Keggin-type phosphometalates are effective catalysts for solvent-free oxidation with urea–H2O2 by dispersing on fluorapatite solid phase. In the solid phase system the phosphomolybdate (NH4)3PMo12O40 was more effective than the phosphotungstate (NH4)3PW12O40, whereas the latter was much superior to the former in the liquid-phase reaction with aqueous H2O2. In situ formation of novel peroxo-type species from (NH4)3PMo12O40/FAp and urea–H2O2, which may lead to the high catalytic activity in the solid phase system, was observed by 31P solid-state NMR.
Keywords :
Phosphomolybdates , Fluorapatite , epoxidation , environmentally benign catalyst , Urea–H2O2 , peroxo species